Apparatus for fastening screw necks to can tops



June 11, 1963 T. P. GARDNER 3,093,102

APPARATUS FOR FASTENING SCREW NECKS TO CAN TOPS Filed Dec. 23, 1958 6Sheets-Sheet 1 Tuzr] June 11, 1963 T. P. GARDNER APPARATU FOR FASTENINGSCREW NECKS TO CAN TOPS Filed Dec. 23, 1958 6 Sheets-Sheet 2 June 11,1963 T. P. GARDNER 3,093,102

APPARATUS FOR FASTENING SCREW NECKS TO CAN TOPS Filed Dec. 25, 1958 eSheets-Sheet s a E mm 55 a June 11, 1963 T. P. GARDNER APPARATUS FORFASTENING SCREW NECKS TO CAN TOPS Filed Dec. 25, 1958 6 Sheets-Sheet 4June 11, 1963 T. P. GARDNER APPARATUS FOR FASTENING SCREW NECKS TO CANTOPS 6 Sheets-Sheet 5 Filed Dec. 25, 1958 June 11, 1963 Filed Dec. 25,1958 Tuzlb.

TEFL.

T. P. GARDNER 3,093,102

APPARATUS FOR FASTENING SCREW NECKS TO CAN TOPS 6 Sheets-Sheet 6 Thisinvention relates generally to the assembly of screw neck can tops andspecifically to a machine for attaching screw necks to rectangular cantaps.

In the prior art, screw neck fastening to oblong can tops required atwo-step bumping operation calling for the services of four operators,during which operation the closure between the metal of the screw neckand the can top was partially formed in the first step of the operation,and then made secure in a second step of the operation. The duties ofthe operators involved (1) the application of a gasket-filler materialto the end of the screw neck to be attached to the can top; (2) theoperation of a press for the first or crimping step; (3) the operationof another press for the second or bumping step; and (4) the stacking ofthe finished (assembled) can tops into boxes for transportation toanother department in which they were utilized in making rectangularcans. A typical daily output of four operators and two presses wouldamount to approximately 8,000 units.

By mechanical operation of steps (2) and (3) above, only two operatorsare required to provide for the supply of screw necks and can tops andfor the removal of assembled can tops for transfer to shipping boxes, asWell as for starting and stopping the bumping machine as necessary, withan increase in daily production from 2,000 units per operator to 9,000units per operator.

Accordingly, it is an object of this invention to provide an improvedmachine to fasten screw necks to can tops.

It is another object of the invention to provide an improved machine forattaching screw necks to can tops wherein the can tops are [movedautomatically into proper position for the assembly with the screwnecks.

Still another object of the invention is to provide an improved screwneck bumping machine having means for the proper positioning of screwnecks on can tops during their assembly.

And another object of this invention is to provide an improved bumpingmachine for fastening screw necks to can tops wherein the proper degreeof contact is obtained between these elements and the machine during theassembly of the screw neck and can top in two simultaneous but differentfastening operations.

These and other objects, features and advantages of the invention willbecome apparent from the following description when read in conjunctionwith the accompanying drawings in which:

FIG. 1 is a diagrammatic side elevation view of the machine forfastening screw necks to can tops, with a general showing of themechanism for actuating the can top feed means and the means for raisingthe dies for the bumping operation;

FIG. 2 is a diagrammatic end elevation view of the machine of FIG. 1,with a general showing of the screw neck positioning means;

FIG. 3 is a diagrammatic partial plan view of the machine of FIG. 1,showing several of the stations of the can tops as they are fed along;

FIGS. 30 and 3b are, respectively, plan and elevation views of the cantop separator and feed elements taken at the section 3b3b of FIG. 3.

FIG. 4 is a diagrammatic plan view of the machine of FIG. 1, with ageneral showing of the automatic stop Patented June 11, 1963 ice devicesand the cams for actuating the means for properly positioning the screwnecks on the can tops;

FIG. 5 is a diagrammatic plan view showing can tops at the variousstations and the screw necks positioned on them as they are fed throughthe machine;

FIG. 6 is a cross section of the screw neck resting in place on the cantop prior to the first step of the bumping operation for fastening tothe can top;

FIG. 7 is a cross section of the seam between the can :op and screw neckafter the first or crimping operaion;

FIG. 8 is a view similar to FIG. 7, showing the finished leak-proof seamwhen the screw neck is fixed to the can top after the second bumpingoperation;

FIG. 9 is a plan view of the mechanism by which the screw tops are movedinto position over the can top;

FIG. 10 is a side elevation view of FIG. 9 showing the means by whichvertical motion of the screw neck feed arm is obtained;

FIG. 11 is an end elevation view of FIGS. 9 and 10 showing more detailsof the means by which the screw necks are placed in position on the cantops;

FIG. 12 is a diagrammatic view as a geenral end elevation through asection of the machine of 'FIG. 1, to show the dies in position readyfor bumping; and

FIG. 13 is a cross section of a side elevation of FIG. 12 showing themeans by which the dies are raised into bumping position.

The objects of the invention are achieved by the use of an apparatushaving a mechanism for automatically placing screw necks in properposition on can tops as the latter are passed at regularly spacedintervals through a two-step bumping operation using dies having theproper degree of contact to fasten screw necks with a leak proof jointto can tops.

Referring to FIGS. 1, 2 and 3 of the drawings to follow the descriptionof the can top feed mechanism, the actuating means therefor includes thefeed bar lever arm at 10 and the crank at 11, which imparts the requiredoscillating motion to the feed assembly as it moves in slot 12 in thelever arm 10, while the latter moves radially about the pivot rod at 13.Connecting bars at 14, 14, are fastened to opposite ends of crank pin 15extending through the eye end of the lever arm 10 and are joined at 16',16, to the feed bars 17, 17, FIG. 2, which travel in the feed bar slides18-, 18, and retained in position by the feed bar gibs at 1?, 19. Thecan tops are fed from the holder at 20, FIGS. '1 and 3, by means of theseparator and feed elements, 21 and 22 respectively, FIG. 3 supported bythe feed bars, and detailed in FIGS. 3:: and 3b, constituting the meansby which the :bottom can top is separated from the stack and startedmoving along the feed line.

The stacked can tops without the screw necks rest upon the feed elements22, 22. When the feed mechanism moves to the left from the positionshown in FIGS. 3, 3a or 3b, the separators 21, 21, each with a knifeedge at 21a, 21a, on the end facing the can tops, slide over the bottomcan top of the stack and separate it therefrom. When the slide assemblystarts to move to the right as in FIG. 3, the feed elements 22, 22,contact the can top at the edges 22a, 22a, and shove it into theposition indicated as #1 in FIG. 3, The separator and feed elements (21and 22) move together and are positioned in the slides relative to eachother with the knife edges 21a, 21a, slightly overlapping the edges 22a,22a, thus permitting the separated can top to fall below separatorelement 21 and in proper position with respect to the feed element 22for movement thereby when the elements 21 and 22 return to the right asshown in FIG. 3.

On the next reciprocating cycle of the feed mechanism,

the can top which has been extracted from the bottom of the stack andnow in the #1 position, is pushed to the #2 position and on eachsucceeding cycle, into each succeeding position until it has completedits travel through the machine, during which time a screw neck has beenfastened to it. Spring actuated dogs at 23, carry the can tops along thefeed mechanism on the feed stroke and are retracted into recesses in thesides of the feed bars on the separating stroke, during which time, thecan tops are held in position by the stop dog at 24 at the can top feedstation, and stop dogs at 25 at the numbered positions down along theline. The spacing between the can tops is fixed by the radius of thecrank 11, the length of the lever arm 10 and the distance from the axisof the crank to the pivot rod 13. The position of the slide bars 17, 17,relative to the lever arm 10 may be varied by means of the adjustableconnecting links 14a, Mo on each connecting bar.

The same spacing between can tops is used for all sizes of tops.However, when larger can tops are to be processed, the top holder at 20may be enlarged to take care of the greater length and the distancebetween the slides may be increased by adjusting one bar slide at thenecessary distance away from the other.

The apparatus for placing the screw necks in proper position on the cantops will now be described, referring to FIGS. 9, l and 11. Screw necksare delivered through the screw neck chute extension at 30 through thenose at 30a, FIG. 2, which is arranged so that the engaging plug 31 ofthe feed apparatus engages the screw neck lying therein and moves itquickly into such position that it covers exactly the opening in the cantop in position #3. The horizontal are through which this engaging plug31 swings is shown on FIG. 9.

A feed arm 32 pivoting above its driver hub 33 carries the plug 31 atits outer end for engagement with a screw neck lying in the nose of thechute and moves it into position on a can top. The required horizontalmotion is obtained through the action of the grooved cam 34, FIGS. 9 and10, on the lever 35 and the feed arm shaft 35a. When the screw neck isin proper position on the can top, the plug 31 is lifted from the screwneck and returned in lifted position to a point above another screwneck, which will have moved into position in the nose of the chute, andthen lowered to engage this screw neck. The lifting and dropping motionof feed arm 32 is obtained by means of feed arm lifter lever arm 36, thelifter rod link 37, the lifter rod 38 and the feed arm lifter as at 39working on pivot screw 40 in the extension 32a of feed arm 32. The feedarm lifter 39 is pulled down by action of the cam 41 and the roller 36amounted on arm 36 pivoted about the lifter lever stud at 42. Therelative positions of the earns 34 and 41 must be such that there isperfect synchronization between the lifting and the swinging actionrequired to transfer a screw neck from the nose of the chute to theproper position on a can top and then return plug 31 to the nose chutein perfect sequence with the stop and go, i.e. reciprocating, motion ofthe can tops as they pass through the #3 position on the machine. Withcam 41 in the position as shown, the feed arm 32 would be lifted. Thecam 41 should be rotated 90 clockwise for the lifter rod and lifter tobe in the position shown in FIG. 11 and the feed arm 32 to be inhorizontal position.

As mentioned previously, the screw necks are fastened to the can tops ina two-step bumping operation. Referring to FIGS. 12 and 13, in the firststep of the operation, punch 50' engages the die 51 to crimp the metalto the screw neck around the metal of the can top, as shown in FIG. 7,and although the screw neck can be turned by hand, it is securelyfastened to the can top. In the second step of the operation, the punch52 engages die 53 to flatten the crimped edge and to obtain a permanent,leak-proof seal. If the dies 51, 53 were to be rigidly fixed in positionfor bumping, the can tops could not be fed over them properly. If theywere to be kept recessed enough for the can tops to clear them, then thetops would be bent in the bumping operation. Therefore, it is necessaryfor the dies to be clear of the can tops as they are pushed intoposition for bumping before the bumping operation occurs. This is doneby means of the die lifting apparatus shown in section in FIG. 13.

The dies 51, 53, are mounted in die holders 54 and 55 respectively,which are free to move vertically. The die holders rest on a bar 56 inwhich there are recesses 54a, 55a, of such depth that the can tops willclear the die bolder when they are in position shown in FIG. 13. Whenthe bumping operation is about to take place, the bar or die lifter 56is moved to the right in FIG. 13 by means of link 56a and lever 57actuated by the grooved die lifting cam 58 and the cam roll arm 59,pivoted on shaft 59a, FIG. -1, the die holders being lifted by adistance equal to the depth of the recesses in bar 56. This brings thedies into contact with the bottom of the can top and provides a firmfoundation on which contact between the punches and the dies can bemade. Studs 60, 60, on the sides of the die holders are joined to thedie holder support 61 by steel springs 62, 62, to insure rapid return ofthe die holders to the recessed position, when bar 56 moves back intothe position shown in FIG. 13.

The method used to obtain the proper degree of contact between thepunches and the dies will be described by reference to FIGS. 2 and 13.The connecting rod at R has the usual means T for adjusting the lengthof the rod. The :length of the punch 50 for the first step of theoperation is variable by means of the adjustment 50a. The desired degreeof contact between the punches and the dies is obtained by firstshortening punch 50 by the adjustment 50a, then making the adjustment inthe connecting rod adjustment T, so that the punch 52 makes the desireddegree of contact with the die 53 when the screw neck and the can topare in bumping position for the permanent seam. With the position of thepunch sup port 70 and so punch 52 fixed by this operation, the positionof punch 50 is adjusted by means of the adjusting device 50a to give thedesired degree of contact between the punch 50 and the die 51 when screwnecks and can tops are in the first step of the operation. If it werenot for the adjustment at T and at 50a, it would be virturallyimpossible to obtain the desired degree of contact in the twosimultaneous bumping operations disclosed herein.

The machine is equipped with several devices which can either shut itdown or halt the action of the screw neck mechanism in case either thecan tops or screw necks are not available or if either of these is notin proper alignment. If there is no can top in position #1, the leveractuated switch at 80, FIG. 4, shuts the unit down by energizing thesolenoid 81, FIG. 1, connected to the release lever 81a. If the can topsare not in proper position on the feed bars 17, 17, i.e. properlyretained between the feed bar gibs 19, 19, the hinged flap at 82, FIG. 4is lifted, and, by means of a microswitch at 83, actuates solenoid 81,FIG. 1, to stop the machine.

The device indicated at 84, FIG. 4, with arcuate ends, is mounted sothat it will rest on the screw necks when they are in position on thecan tops. If there is no screw neck on the can top moving under thisdevice or if the screw neck is not in the proper position on the cantop, this device actuates the microswitch at 85, FIG. 4, to energize thesolenoid 81 and stop the machine. Solenoid 81 also may be actuated bythe stop switch 86, FIG. 1, on the front end of the machine.

This bumpingmachine may be driven from an overhead shaft, but asdisclosed herein, an individual motor drive is provided. Referring toFIG. 2, there is disclosed a base 2 mounted on the machine, a motorsupport 3, for supporting the motor 4 in proper position relative to thefly wheel W, with the connection of the flywheel W to the motor 4 beingmade by means of the coupling at 5 and a groove pulley at 6. The powerfor operating the various cam shafts is taken off the fly wheel shaft X,FIG. 2, by means of a chain drive at Y and the sprocket connection at Z.

Referring back to FIGS. 1 and 2 there is disclosed also a screw neckhopper at A and a sorter wheel at a, while the frame on which thebumping machine is built is shown dotted at F, FIG. 1.

It is common practice in the handling of can tops and similar smallmetal pieces to hold them in proper position in machines by means ofmagnets. Showing of such is omitted in the present figures, although itis mentioned that they are located beneath the several positionsindicated in FIG. 3 and midway between the slide bars. The faces of themagnets lie just below the top of the feed bar so that the magneticforces which they create hold the can tops firmly against the slide bar.

Thus there has been shown and described, :a machine having the variousoperations of automatically withdrawing a can top from a supply stockand feeding it by a reciprocating can top feed mechanism into positionswhere a screw neck is sealed thereto with a leak proof seam in atwo-step bumping operation, two separate steps of the bumping operationbeing aeomplished simultaneously.

Obviously, many modifications and variations in the invention ashereinbefore set forth may be made without departing from the spirit andscope thereof, and therefor only such limitations should be imposed asare indicated in the appended claims.

I claim:

1. In combination, in an apparatus for the automatic assembly of screwnecks to can tops, means for positioning can tops in a feed lineincluding longitudinally reciprocating members and means for separatingindividual can tops from a plurality thereof including separator andfeed elements, said elements being supported by said reciprocatingmembers whereby their movements cause individual can tops to feed alongsaid feed line, reciprocating crank and lever means interconnected withsaid reciprocating members for actuation thereby, each of the separatorelements having a knife edge in the direction of separating motion forseparating individual can tops from said plurality thereof when saidreciprocating members move in one longitudinal direction, the feedelements being mounted in spaced relationship to the separator elementsfor receiving separated individual can tops for movement into positionsin said feed line when said reciprocating members return longitudinallyto starting position, the knife edge of each of said separator elementsending adjacent the downstream edge of each of said feed elementswhereby an individual can top is dropped into position for engagement bythe latter for movement to feed positions, the improvement comprising ascrew neck positioning struc ture for placing screw necks on can topsfed automatically along the feed line comprising means havingoscillatory rotational and translational movement for removing a screwneck from a supply thereof and positioning the same on a can topincluding a pivoted lever arm having a plug for engagement with saidscrew neck and a pivot screw at the opposite end of said lever arm,means for imparting rotational movement to said pivoted lever armincluding a grooved cam and a lever member controlled thereby and meansfor imparting translational movement to said pivoted feed arm afterrotational movement thereof comprising pivoted lever members acting onsaid pivot screw and a compound cam actuating said pivoted levermembers, said grooved cam and said compound cam being related inposition for synchronization between the rotational and translationalmovements, said cams being actuated from a cam shaft providing automaticfeed of spaced can tops.

2. In a machine for fastening screw necks to can tops in a two stepoperation by automatic feeding and positioning of can tops along a feedline, reciprocating means for separating individual can tops from asupply thereof and for feeding the separated can tops, saidreciprocating means being joined to interconnected lever arm and crankmembers for their reciprocating movement and comprising can topseparator and feed means including a first member having a knife edge inthe direction of separation motion, and a second member in spacedrelationship to said first member arranged so that the separated can topis positioned in the path of the reciprocating return movement wherebyfeeding of said separated can top to a forward position is obtained in adirection opposite the direction of separating motion, and means forremoving a screw neck from a supply thereof, placing the same on aproperly positioned can top and returning to position for removing asucceeding screw neck including a pivoted feed arm with a neck engagingplug and means for swinging said feed arm from neck removing position toneck placing position and return to neck removing position comprisinginterconnected lever members and a grooved cam acting thereon, and meansfor lifting said pivoted feed arm following neck positioning fordisengagement therewith, connected lever members in contact with saidpivoted feed arm and a compound cam for actuating said pivoted levermembers, said reciprocating means for separating and feeding can topsand the screw neck positioning structure being interconnected at thesource of power therefor, the improvement comprising means forsimultaneously applying an initial crimp lock fastening between parts ofa unit comprising a screw neck positioned on a can top in said feed lineand permitting loose frictional movement between said neck and said cantop and applying a final permanent seal by a bumping device to thepreceding unit of said feed line to which the initial crimp lockfastening has been applied, said last mentioned means including a punchand die assembly therefor with a plurality of corresponding punches anddies housed therein including means for lowering said dies as said cantops and screw necks positioned thereon are fed into bumping positionand for raising said dies in proper sequence for the bumping operationincluding a sliding die lifting member and a die holder housing thesame, said lifting member having a groove for receiving the end of saiddie, and means for sliding said lifting member including lever and cammeans actuated by the means actuating the can top feed mechanism and thescrew neck positioning mechanism.

3. In the machine as defined in claim 2, the first punch with respect tothe approaching can tops housed in said punch and die assembly havingmeans for adjusting the amount of contact between the first punch anddie required for the initial crimping operation of fastening a screwneck to a can top.

References Cited in the file of this patent UNITED STATES PATENTS1,010,617 Gray Dec. 5, 1911 1,310,837 Murch July 22, 1919' 1,340,634Soderstrom et a1. May 18, 1920 1,620,447 Donovan Mar. 9, 1927 1,778,540Wikstrom Oct. 14, 1930 1,797,418 Hothersall Mar. 24, 1931 1,811,162Troyer June 23, 1981 1,947,610 McNamara Feb. 20, 1934 2,085,767 ReidJuly 6, 1937 2,167,654 Hothersall Aug. 1, 1939 2,433,066 Rund Dec. 23,1947 2,589,769 Brucker Mar. 18, 1952

1. IN COMBINATION, IN AN APPARATUS FOR THE AUTOMATIC ASSEMBLY OF SCREWNECKS TO CAN TOPS, MEANS FOR POSITIONING CAN TOPS IN A FEED LINEINCLUDING LONGITUDINALLY RECIPROCATING MEMBERS ANDMEANS FOR SEPARATINGINDIVIDUAL CAN TOPS FROM A PLURALITY THEROF INCLUDING SEPARATOR AND FEEDELEMENT, SAID ELEMENTS BEING SUPPORTED BY SAID RECIPROCATING MEMBERSWHEREBY THEIR MOVEMENTS CUASE INDIVIDUAL CAN TOPS TO FEED ALONG SAIDFEED LINE, RECIPROCATING CRANK AND LEVER MEANS INTERCONNECTED WITH SAIDRECIPROCATING MEMBERS FOR ACTUATION THEREBY, EACH OF THE SEPARATORELEMENTS HAVING A KNIFE EDGE IN THE DIRECTION OF SEPARATING MOTION FORSEPARATING INDIVIDUAL CAN TOPS FROM SAID PLURALITY THEREOF WHEN SAIDRECIPROCATING MEMBERS MOVE IN ONE LONGITUDINAL DIRECTION, THE FEEDELEMENTS BEING MOUNTED IN SPACED RELATIONSHIP TO THE SEPARATOR ELEMENTSFOR RECEIVING SEPARATE INDIVIDUAL CAN TOPS FOR MOVEMENT INTO POSITIONSIN SAID FEED LINE WHEN SAID RECIPROCATING MEMBERS RETURN LONGITUDINALLYTO STARTING POSITION, THE KNIFE EDGE OF EACH SEPARATOR ELEMENTS ENDINGADJACENT THE DOWNSTREAM EDGE OF EACH OF SAID FEED ELEMENTS WHERE BY ANINDIVIDUAL CAN TOP IS DROPPED INTO POSITION FOR ENGAGEMENT BY THE LATTERFOR MOVEMENT TO FEED POSITIONS, THE IMPROVEMENT COMPRISING A SCREW NECKPOSITIONING STRUCTURE FOR PLACING SCREW NECKS ON CAN TOPS FEDAUTOMATICALLY ALONG THE FEED LINE COMPRISING MEANS HAVING OSCILLATORYROTATIONAL AND TRANSLATIONAL MOVEMENT FOR REMOVING A SCREW NECK FROM ASUPPLY THEREOF AND POSITIONING THE SAME ON A CAN TOP INCLUDING A PIVOTEDLEVER ARM HAVING A PLUG FOR ENGAGEMENT WITH SAID SCREW NECK AND A PIVOTSCREW AT THE OPPOSITE END OF SAID LEVER ARM, MEANS FOR IMPARTINGROTATIONAL MOVEMENT TO SAID PIVOTED LEVER ARM INCLUDING A GROOVED CAMAND A LEVER MEMBER CONTROLLED THEREBY AND MEANS FOR IMPARTINGTRANSLATIONAL MOVEMENT TO SAID PIVOTED FEED ARM AFTER ROTATIONALMOVEMENT THEREOF COMPRISING PIVOTED LEVER MEMBERS ACTING ON SAID PIVOTSCREW AND A COMPOUND CAM ACTUATING SAID PIVOTED LEVER MEMBERS, SAIDGROOVED CAM AND SAID COMPOUND CAM BEING RELATED IN POSITION FORSYNCHRONIZATION BETWEEN THE ROTATIONAL AND TRANSLATIONAL MOVEMENTS, SAIDCAM BEING ACTUATED FROM A CAM SHAFT PROVIDING AUTOMATIC FEED OF SPACEDCAN TOPS.